Open and closing grippers on an abb dual arm robot (IRB 14000 yumi)

I have been trying to program the grippers of an abb robot to open and close in order to pick up objects, but I have not been able to figure it out. Every tutorial I find that shows programming with a gripper assumes you already have signals set up in order to open and close grippers, but I don't know how to set these up, or it shows how to do this in a simulation. I have been able to set up a digital signal in order to open the gripper with code, but I can't figure out how to get them closed with code. Could someone point me to a tutorial or explain how to set up digital signals for a smart gripper on an abb robot in order to program them to open and close?